FIX WEBUI problems with datetime-local input data

The browser can send the form value in different formats, either
including the seconds or not. It usually does not include seconds if
seconds is "00". This means that value should be parsed against two
different formats.

refs #35

larigira/timeform_base.py

@@ -1,3 +1,6 @@
+import logging
+log = logging.getLogger('timeform_base')
+
 from datetime import datetime
 from pytimeparse.timeparse import timeparse
 
@@ -10,31 +13,43 @@ import wtforms.widgets
 class DateTimeInput(wtforms.widgets.Input):
     input_type = 'datetime-local'
 
+    def __call__(self, field, **kwargs):
+        # every second can be specified
+        return super(DateTimeInput, self).__call__(field, step='1', **kwargs)
+
 
 class EasyDateTimeField(Field):
     '''
     a "fork" of DateTimeField which uses HTML5 datetime-local
-    The format is not customizable, because it is imposed by the HTML5 specification
+
+    The format is not customizable, because it is imposed by the HTML5
+    specification.
+
+    This field does not ensure that browser actually supports datetime-local
+    input type, nor does it provide polyfills.
     '''
     widget = DateTimeInput()
+    formats = ('%Y-%m-%dT%H:%M:%S', '%Y-%m-%dT%H:%M')
 
     def __init__(self, label=None, validators=None, **kwargs):
         super(EasyDateTimeField, self).__init__(label, validators, **kwargs)
-        self.format = '%Y-%m-%dT%H:%M:%S'
 
     def _value(self):
         if self.raw_data:
             return ' '.join(self.raw_data)
         else:
-            return self.data and self.data.strftime(self.format) or ''
+            return self.data and self.data.strftime(self.formats[0]) or ''
 
     def process_formdata(self, valuelist):
         if valuelist:
             date_str = ' '.join(valuelist)
+            for fmt in self.formats:
                 try:
-                self.data = datetime.strptime(date_str, self.format)
+                    self.data = datetime.strptime(date_str, fmt)
+                    return
                 except ValueError:
-                self.data = None
+                    log.debug('Format `%s` not valid for `%s`' %
+                              (fmt, date_str))
             raise ValueError(self.gettext(
                 'Not a valid datetime value <tt>{}</tt>').format(date_str))